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Table Of Contents
EVOC 20 PolySynth Global Parameters
The parameters at the top left of the interface determine the keyboard mode and number
of voices used by the EVOC 20 PolySynth.
Poly button/Voices field: When Poly is selected, the maximum number of Voices can be
set in the numeric field.
Mono/Legato buttons: When Mono or Legato is selected, the EVOC 20 PolySynth is
monophonic, and uses a single voice.
In Legato mode, Glide (see EVOC 20 PolySynth Tuning and Pitch Parameters) is only
active on tied notes. Envelopes are not retriggered when tied notes are played (single
trigger).
In Mono mode, Glide is always active and the envelopes are retriggered by every
note played (multi trigger).
Unison button: Enables or disables Unison mode.
In Unison/Poly mode—where both the Unison and Poly buttons are active—each
EVOC 20 PolySynth voice is doubled, which cuts polyphony in half (to a maximum
of 8 voices, shown in the Voices field). The doubled voices are detuned by the amount
defined with the Analog knob.
In Unison/Mono mode—where both the Unison and Mono or Legato buttons are
active—up to 16 voices can be stacked and played monophonically. The Voices field
displays the number of stacked voices that will be heard.
Important: Stacking voices in Unison/Mono mode significantly increases the EVOC 20
PolySynths output volume. To avoid overloading the instrument channel strip output,
you should initially set a low Level slider value and gradually bring it up (see EVOC 20
PolySynth Output Parameters).
EVOC 20 PolySynth Formant Filter Parameters
The EVOC 20 PolySynth features two formant filter banks—one for the Analysis section
and one for the Synthesis section. Each bank can house up to 20 individual filters. In
essence, the entire frequency spectrum of an incoming signal is analyzed by the Analysis
section and divided equally into a number of frequency bands. These analysis filter bands
are mirrored by a corresponding number of bands in the synthesis filter bank. Each filter
bank controls the peak levels—the formants—within these frequency bands. For more
information, see How Does a Vocoder Work?, and A Short Primer on Formants.
151Chapter 7 EVOC 20 PolySynth